Blowoff valve assemblies with integrated pressure switches are well known in the prior art. An example of such an assembly is disclosed in U.S. Pat. No. 5,153,396 (the '396 patent) to Cummings.
The assembly of the '396 patent includes a diaphragm which separates a refrigerant connection for connection to a refrigerant from an ambient port open to atmosphere. The diaphragm senses the pressure of the refrigerant. A switch is operatively connected to the diaphragm and is closed when the pressure of the refrigerant is at a standard level. As pressure of the refrigerant increases to a predetermined lower threshold, the switch opens to shut down a compressor in an attempt to stop the increase in pressure of the refrigerant. However, if the pressure of the refrigerant increase further to a predetermined upper threshold, an array of pins, positioned around the diaphragm, will puncture the diaphragm. The diaphragm then ruptures, allowing the refrigerant to ventilate from the refrigerant connection to the ambient port.
Although the assembly of the '396 patent may be effective apparatus to ventilate refrigerant from an air conditioning system in response to a high pressure condition, there remains an opportunity for an assembly for detecting a leak of a refrigerant and quickly ventilating the refrigerant to atmosphere.